Rotatable gas filter



Oct. 6, 1931. B. RICHTER ROTATABLE GAS FILTER Filed July 29, 1929 edema or e, 1931 UNITED "sTA'rEs BIRNEABD RIGHT, 01' BERLIN, GEBIANY nor-manna ens 11mm.

Agpucationfled July 29, Serial 10. 381914, and in Germany Augult 87, 1928.

This invention relates to a metal filter for cleansing air and gas the peculiarit of which is the automatic removal of the ust separated. Filters of this kind have an endless a travelling band running overpulleys at the top andat the bottom and passln through an oil hath in which the separated ust is automatically washed 0E and the filter element again saturated with oil. These filters are for example built. up of individual plates with special profile so that a kind of link chain is formed, or the are composed of a number of elements filled ith filtering material moved like paternoster elevators. This last named 5 construction presents various advantages over the first mentioned construction, consisting chiefi therein that the travelling band on the dust aden air side can he moved in upwarddiiection, whereby the dusty filter surface passes into the inside otthe filter Where it comparatively forms a very efiective fine filter. Both constructions have the disadvantage of being expensive. This. disadvantage the construction according to is overcome in the application and atthe same time the advantage of the aternoster movement is utilized hutin an entirely difierent manner.

An embodiment of the invention is illustrated hyway of example in the accompanying drawings in which:

" horizontal. Consequentlly Figs. 1, 2 and 3 are dis ammatic longitudinal sections through dlfierent modifications or. the filter, Fig. 3 showing only the upper portion.

Fig. 4 shows in elevation the arrangement of several plates in a portion on the endless hand. i t

Fig. 5 is a section on line A-B of Fig. 4.

An endless hand a is composed of individual plates l; of any suitable sha e. In-

stead of the plates other known filtering material such as Raschig rings, wire gauze, turning chips or the like may be used. The filtering material according to the invention is not placed vertically to the air current a striking against same but it is arranged horizontally or in a plane inclined towards the separate filtering surfaces 42 are produce on the travelling band and spaces 0 between these surfaces through which the air current passes to the filter elements through which it does not pass in horizontal direction but in approximately vertical direction from below or from above. The space e'is shut ofi by a plate f to prevent the passage of impure gas, which plate also serves as a guide for the air or gas. it is apparent that with this type of construction the depth g of the filtering surface (2' can be considerably larger, i. e. its height plus the height of the space. By this means the great advantage is attained of a much lower build than with vertically arranged iiltering surfaces.

The plate f according to Fig. 2 is oscillatable, and this forms a turther feature of the invention, so'that at the movement of the travelling hand a series of efiects is produced, which result in advantages or great im ortance. The plate f is rota-tahly mounte on the pin a so that it can he hrought either into the position shown in Figs. l and Q or into the position shown in Fig. 3. The plate f may he held in the desired position for example by a weight is by means of which the centre of gravity of the plate is displaced out of the pivot pin e'. 4 At the continued movement of the travelling hand, which should run from the bottom to the top on the side. late after towards the air admission, the passing the upper reversing omt Zautomatically turns over so that to air or gas current must flow through the filter layers of the rear side of the hand which have also been turned, in the same direction from the dusty side to the clean side, as on the front side of the band, so that a carrying ofi of dust in the cleansed air is efiectively prethe air or gas current can pass through one 1 necessitates considerably higher initial cost and a much larger space for building in the filter, which is often not available. Consequently hitherto it was necessary with filter plants in which only a slight loss of pressure was permissible to use cell filterswhich only have a single filtering surface and to renounce the advantages of the automatic operation of the travelling filter.

In Fig. 3 the air need not pass through the filter surface of the rear side of the band. This is attained in that the plates f on the rear side of the band encounter a stop 0 which holds the plates in horizontal position. The air current consequently can no longer flow through the filter layer a! but passes into the pure air compartment through the'space e where it only encounters slight resistance. It is immaterial whether the travelling band passes from the bottom to the top or vice versa on the side of air admission. The filter layers of the front portionof the band may also be periodically put out of operation in a similar'manner y horizontally adjusting the plates. All these difierent possibilities of adjusting the plates may be effected by hand or automatically and instead of by weights, by other known mechanisms such as sprin s, guides or the like.

I c aim 1. A filter for cleansing air and gas with a movable travelling band composed of filter elements, comprising in combination an endless band, a plurality of filter elements arranged horizontally around said travelling band so that the fluid tobe cleansed passes through said filter elements in approximately vertical direction, a plate mounted on the travelling band for guiding the flow. of the fluid fitted between each two filter elements,

said plate passing from the inner lower edge of an upper filter element to the outer top edge of the lower filter element, said plate acting to prevent the fluid to be cleaned from passing through the endless band without passing through the filter elements.

'2. A filter' as specified in claim 1 comprising in combination with the travelling band, guide plates oscillatably niountedton said travelling band and a pivot pin for each guide plate adapted to be positively displaced during the travel of said travelling band so that by said guide plates the fluid current is diverted and flows through the 3. A filter as specified in claim 1, comprisin in, combination with an endless belt and ter elements, plates arranged between each two of said elements, pivot pins carrya ing said plates, and weights adapted to automatically reverse said plates at the top and bottom during the travel of the band.

4. filter as specified in claim 1, com rising in combination with an endless and having filter elements arranged around its surface-and a shut-ofi' plate between each two of these filter elements, means for adjusting said plates so that the fluid current can pass through both sides of the band and for rendering the filter temporarily inoperative.

5. A filter as specified inclaim 1, comprising in combination with the travelling band filter elements and a plate arranged between each two of said elements, stops adapted to engage with and hold said plates on one side of the travel of said band in such a position as to prevent the fluid to be cleansed from passing through the filter elements on this side of the band and to make it flow through the spaces between said filter elements.

. In testimony whereof I afiix my signature.

BERNHARD RICHTER.

reversed filter elements on the rear side of the belt in the same direction as in the front portion from the dust removing side to the clean side. 

